1. Field of the Invention
This invention generally relates to video game systems in which a player manipulates a virtual interface device within a game space, wherein a virtual interface device represents a real interface device that the player within a real space manipulates.
2. Background Information
In conventional video golf games used in the home or in video game arcades, for example, the swinging motion of an object (i.e., the golf club) in the game space is controlled by pushing buttons or by pulling levers. However, controlling objects by manipulating buttons or levers gives a player a feeling that the game is not realistic, and does not provide a game that allows a player to experience the real charm of golf. Accordingly, most people who play video golf games turn out to be people who simple love to play video games. To begin with, commands that instruct which object within the game space is moved and in what direction are assigned to the buttons and levers in advance. Thus, movement of the object by means of the buttons and levers is limited by the combinations of action patterns preset in the game.
On the other hand, golf simulation devices have been offered in which a golf player can practice easily. However, these devices take up too much space and are quite expensive, and thus are not favored by video game arcade operators.
In order to manipulate golf balls more naturally, for example, H10-214155A discloses an input device shaped like a golf club, in which the movement of the input device is detected and the swing motion thereof is input. An acceleration sensor is installed at the inside of the head. If the acceleration level of the head detected by the acceleration sensor exceeds a certain level, the input device determines that the player intends to hit a ball.
However, a full swing of a golf club requires a large amount of space around a player, and it also requires an increase in the space in which the input device is set. In addition, swinging a golf club is risky at a video game arcade because there are often many people present. Moreover, in order to allow a player to naturally enjoy a golf game, it is not enough that a player can hit a golf ball by swinging a golf club. For example, in order to allow a player to hit a ball in a particular direction with a club, it is necessary to create visual factors that provide the player with targets. In addition, when a player plays a real golf game, he chooses his favorite club from amongst a variety of golf clubs and uses it. Accordingly, a golf game in which he uses only one kind of golf club won""t satisfy a golf player, and won""t attract general users other than people who simply like to play video games.
Therefore, an object of the present invention is to provide a video game device that allows a player to feel the charms of a variety of different games. Another object of the present invention is to provide a video game device that does not take up a lot of space. Yet another object of the present invention is to provide a video game device that is safe to use.
According to one aspect of the present invention, a game device is provided in which a real interface device operated by a player within a real space is represented by a virtual interface device in a virtual space. The virtual interface device in the game device includes a virtual contact unit and a virtual operation unit. The virtual contact unit is a portion of the virtual interface device that a virtual player who manipulates the virtual interface device contacts in order to operate the virtual interface device. The virtual operation unit is a portion of the virtual interface device that manipulates an object operated by the virtual interface device.
The game device includes:
(a) position detection means for detecting the position of the real interface device within the real space, wherein the real interface device is shaped like the virtual contact unit, conversion means for converting the detected real position of the real interface device into a virtual position within the virtual space that is a virtual position of the virtual contact unit within the virtual space,
(b) calculating means for calculating the virtual position of the virtual operation unit based on the virtual position of the virtual contact unit,
(c) operating means for moving the virtual operation unit within the virtual space so that its movement follows the movement of the real interface device with in the real space, which repeatedly causes the real position of the real interface device to be detected by the position detective means, the virtual position of the virtual contact unit to be calculated by the converting means, and the virtual position of the virtual operation unit to be calculated by the calculating means.
Assume, for example, that the video game device is a golf game device. The virtual interface device is a virtual golf club within a game space. The virtual contact unit corresponds to the virtual grip and the virtual operation unit corresponds to the virtual head. The real interface device is shaped like a grip of a golf club or that of a mini golf club that is much shorter than a golf club. Or suppose that the video game device is a tennis game device. In this case, the virtual interface device is a virtual tennis racket within a game space. The virtual contact unit corresponds to the virtual grip and the virtual operation unit corresponds to the virtual racket face. The real interface device is shaped like a grip of a tennis racket or that of a mini tennis racket that is much shorter than a tennis racket. Or suppose that the video game device is a baseball game device. In this case, the virtual interface device is a virtual bat. The virtual contact unit corresponds to the grip of the virtual bat and the virtual operation unit corresponds to the upper on third of the virtual bat. The real interface device is shaped like a grip of a bat or that of a mini bat that is much shorter than a baseball bat.
If the video game device is a golf game device, a player swings a grip-type real interface device, then the movement of the virtual head of the virtual golf club is calculated. If the game device is a tennis game device, and a player swings a grip-type real interface device, the movement of the virtual racket face is calculated. If the game device is a baseball game device, a player swings the grip-type real interface device, then the movement of the portion of the virtual bat within the virtual game space that hits a ball is calculated.
According to another aspect of the present invention, the game device further includes:
(a) display means for displaying the virtual operation unit, and
(b) position determining means for determining a display position at which the virtual operation unit is displayed on a screen, based on the virtual position of the virtual operation unit.
In this game device, the operating means causes the real position of the real interface device to be detected by the position detecting device, the virtual position of the virtual contact unit to be calculated by the converting means, the virtual position of the virtual operation unit to be calculated by the calculating means, and the display position of the virtual operation unit to be determined by the position determining means, with these actions being executed repeatedly. The operating means displays the movement of virtual operation unit so that it follows the movement of the real interface device.
Assume, for example, the video game device is a golf game device. The device determines the virtual position of the virtual grip, and calculates a position at which a straight line intersects with the ground of the virtual space. The line goes through the virtual position of the virtual grip and has a certain inclination. The device regards the intersection as the virtual position of the virtual head and displays the virtual head. The game device detects the movements of the grip-type real interface device and displays the movement of the virtual head, which causes the above-mentioned steps at predetermined time intervals. The player can enjoy swinging the real interface device, which is shaped like a golf grip, and will feel as though it is a real golf club. The position within the real space and the position within the game space can be described, for example, with three dimensional coordinates. If the video game device is a golf game device, it preferably includes selecting means for any one of various kinds of virtual golf clubs. In this case, the operating means may display a virtual head corresponding to the kind of the virtual golf club selected. For example, the video game device accepts the selection of the golf club by pushing a button on the video game device, and displays the head of a golf club selected, such as a driver or 5-iron.
According to another aspect of the present invention, the real interface device and the virtual interface are configured to be slightly long (e.g., the length of the grip portion of a golf club, tennis racket, baseball bat, etc.), and the video game device further includes twist detecting means. The twist detecting means detects the degree to which the real interface device is twisted from the standard position around the axis of the real interface device. The operating means displays on a screen the virtual operation unit of the virtual interface device that rotates at the twist angle around the axis of the virtual interface device. Take, for example, a golf game device. A player twists the grip-type real interface device, then the rotation of the virtual head follows the twist action of the player.
According to another aspect of the present invention, the twist detecting means calculates the twist angle of the real interface device based on signals outputted from an acceleration sensor installed on the real interface device.
A three-axis-acceleration sensor may be utilized for detecting the angle at which the real interface device is with respect to the floor, and detecting the angle at which the real interface device is with respect to certain directions on the floor surface. The twist angles can be calculated based on the angles detected.
According to another aspect of the present invention, the video game device is a golf game device. The displaying means of this golf game device further displays scenery at the virtual player""s feet. This golf game device further includes front displaying means for displaying scenery in front of the player. xe2x80x98Frontxe2x80x99 means the direction in which the virtual player is to hit the ball.
The golf game device preferably displays an underfoot view on a lower screen and the front view on a front screen. The underfoot view is the scenery at the virtual player""s feet from the viewpoint of the virtual player. The front view is the scenery from the viewpoint spreading out in front of the virtual player. The viewpoint may be calculated based on the virtual position of the virtual contact unit. The underfoot view and the front view can be created by making a perspective-projection transformation in the game space.
According to yet another aspect of the present invention, the game device further includes
(a) display controlling means for generating an underfoot view and a front view and displaying them by utilizing the displaying means and the front displaying means, wherein the views are from the virtual player""s viewpoint and calculated from the virtual position of the virtual contact unit, and
(b) underfoot view storing means for storing an underfoot view whose resolution is higher than that of an underfoot view generated by the display controlling means. The display controlling means of the game device controls the underfoot views so that the underfoot view stored in the underfoot view storing means is displayed on behalf of the underfoot view generated by the display controlling means.
The underfoot view generated by perspective-projection transformation based on the data composing the game space is too rough to display it as an underfoot view. Thus, the player feels incongruous with the underfoot view if it is displayed at his feet. This is because it is natural for a player that resolution of an underfoot view close to him is higher than that of front view far from him. Thus, the game device stores the data for an underfoot view in advance and displays it on the screen. For example, an underfoot view of a fairway is displayed if the virtual player is on a fairway, and an underfoot view in a bunker is displayed if the virtual player is in a bunker.
According to yet another aspect of the present invention, the game device further includes:
(a) display controlling means for displaying an underfoot view and a front view by utilizing the displaying means and the front displaying means, wherein the views are from the virtual player""s viewpoint (hereinafter, virtual viewpoint) that is calculated based on the virtual position of the virtual contact unit,
(b) view controlling means for shifting the viewpoint for catching the front view from the virtual viewpoint, wherein the shift is executed whether the front view is close to or far from the virtual player. The game device shifts the viewpoint position for the front view when the virtual player is at the tee and looks in the direction of the green, and when the virtual player on a green and looks in the direction of the cup. This is in order not to have the player feel incongruence when the underfoot view and the front view are connected. The view controlling means preferably shifts the viewpoint for the front view to a point that is continuously connected with the underfoot view from the virtual viewpoint when the front view is close to the virtual player. Accordingly, if a front view is close to the virtual player, a front view is displayed that is continuous with the underfoot view from the virtual viewpoint.
According to yet another aspect of the present invention, the position detecting means further includes:
(a) at least a pair of light-detecting means for detecting light from light emitting means or light reflecting means, and measuring means for measuring the position of the light emitting means or the light reflecting means and outputting the measurement result to the conversion means, wherein the light emitting means and/or the light reflecting means are installed in or on the real interface device.
According to another aspect of the present invention, the calculating means determines the virtual position of the virtual operation unit by regarding it as a position at which a straight line intersects with the ground of the virtual space, wherein the line goes through the virtual position of the virtual contact unit, and is at an angle (hereinafter, virtual inclination angle xcfx86) with a standard plane in the virtual space.
Assume, for example, a golf game device. The virtual inclination angled) maybe an average value of the angle between the angle at which a golf club is normally held by an ordinary golf player and the ground. Or the virtual inclination angle xcfx86 may be the angle between the position that a grip-type real interface device is normally held by an ordinary player and the floor. In a tennis game device, the virtual inclination angle xcfx86 may be an average value of the angle between a tennis court and the position of the grip when an ordinary tennis player hits a tennis ball.
According to yet another aspect of the present invention, the video game device further includes inclination detecting means for detecting an angle (hereinafter, real inclination angle) between the real interface device and the standard plane in the real space. The calculating means of the game device calculates the virtual position of the virtual operation unit by regarding the real inclination angle detected as the virtual inclination angle xcfx86. An example of an inclination detecting means includes a three-axis acceleration sensor installed in the grip-type real interface device.
According to yet another aspect of the present invention, the inclination detecting means calculates the real inclination angle of the real interface device based on signals outputted from an acceleration sensor installed in the real interface device.
The angle between the real interface device and the floor surface, and the angle between the real interface device and a certain direction on the floor surface, can be detected by utilizing an acceleration sensor such as three-axis-acceleration sensor.
According to another aspect of the present invention, the game device further includes:
(a) trajectory storing means for storing the virtual positions of the virtual operation unit taken at predetermined time intervals xcex94T1,
(b) area determining means for determining whether the latest stored virtual position of the virtual operation unit is in a hit area in which the object operated by the virtual interface device exists,
(c) stay determining means for determining whether the virtual operation unit has been in consecutive existence for a prescribed stay time Ts or more, based on the virtual positions stored, when the latest virtual position of the virtual operation unit exists in the hit area, and
addressing means for determining that the player is addressing the ball when the virtual operation unit has been in consecutive existence in the hit area for the prescribed stay time Ts or more.
Take, for example, a golf game. The hit area is a circle having a radius r and having a golf ball placed in the center thereof. If the virtual head has been in consecutive existence in the hit area for a prescribed stay time Ts or more, the player is regarded to be addressing the ball. The hit area may become larger or smaller according to kinds of the virtual golf club used. For example, the hit area becomes smaller if the virtual golf club is changed from a driver to an iron, or a putter. Ordinary golf players are supposed to change their swings according to the kind of golf clubs used. Accordingly, setting hit areas corresponding to the kind of golf clubs used allows a game player using the grip-type real interface device to swing without feeling any incongruity. Likewise, the game device determines the player is ready to hit the ball in a tennis game device and the like.
According to yet another aspect of the present invention, the game device further includes:
(a) passage determining means for determining whether the virtual operation unit has passed through the hit area when the player is addressing the ball,
(b) speed determining means for determining whether the passage time is at or below the prescribed passage time Tp when the virtual operation unit has passed through the hit area, and
(c) operation determining means for determining whether the player has manipulated the object by means of the virtual interface device when the passage time is at or below the prescribed passage time Tp.
Take, for example, a golf game situation in which the virtual head has passed through the hit area with a speed faster than the prescribed speed after the player""s address. In this case, the player is regarded to have hit the ball. If the passage speed is too slow, the player is regarded to have made a practice swing or that he has made a movement that is unrelated to his swing. Then, the ball is not moved and remains in place. The prescribed passage time Tp may fluctuate corresponding to the kind of virtual golf clubs used. For example, the prescribed passage time Tp is set to be relatively short for a driver and it is set to be relatively long for a putter. Controlling the prescribed passage time Tp in consideration of the differences between the different swings used with various kinds of golf clubs allows the player to swing naturally with the real interface device.
According to another aspect of the present invention, the game device further includes:
(a) trajectory determining means for determining the trajectory of the virtual operation unit in the hit area based on the data stored in the trajectory storing means, when the operation determining means determines that the player has manipulated the object, and
(b) trajectory calculating means for calculating the trajectory of the object, based on the trajectory of the virtual operation unit.
The trajectory calculating means moves the ball if the operation determining means determines that the ball was hit, even though the trajectory of the virtual head may not have hit the golf ball. The trajectory of the ball is calculated based on the swing direction. In other words, it is calculated based on the trajectory of the virtual head.
According to another aspect of the present invention, the real interface device and the virtual interface device is configured to be somewhat long and the game device further includes:
(a) twist detecting means for detecting the angle at which the real interface device is twisted from a standard position around the longitudinal axis of the real interface device,
(b) trajectory determining means for determining the trajectory of the virtual operation unit in the hit area based on the data stored in the trajectory storing means, when the operation determining means determines the player has manipulated the object, and
(c) trajectory calculating means for calculating the trajectory on which the object has moved, based on the trajectory of the virtual operation unit and the twist angle detected.
In a golf game, for example, the trajectory calculating means calculates the trajectory of the ball in consideration of the twist angle, i.e., the direction of the face of the virtual head, in addition to the swing direction. In a tennis game device, the trajectory calculating means calculates the trajectory of the ball in consideration of the direction of the racket, which is changed when a player slices or drives. Moreover, the operation determining means determines that the player has manipulated the object when the twist angle is within the prescribed twist angle and the passage time is in the range of the prescribed passage time Tp. In other words, the operation determining means determines the player didn""t hit the ball if he has twisted the grip-type real interface device too much, even though the player had addressed and had swung at the speed that is faster than the prescribed speed. Likewise, the operation determining means determines that the player didn""t hit the ball if he had twisted the virtual tennis racket too much in a tennis game device.
According to yet another aspect of the present invention, the operation determining means determines the player has manipulated the object when the distance between the trajectory of the virtual operation unit and the object is in the range of a permissible gap and the passage time is at or below the prescribed passage time Tp.
The operation determining means determines that the player has swung and missed if the trajectory of the virtual head missed the ball by too much, even though the virtual head had passed through the hit area. This is because it will not feel realistic to a player if the ball has moved in such situations. Likewise, in a tennis game device, the operation determining means determines that the player has swung and missed if the virtual racket face missed the ball by too much, even though the virtual racket face has passed through the hit area. The range of permissible gap in the golf game can change with the kind of the virtual golf clubs used. Take, for example, a situation in which the player swings a driver and the virtual head hits the golf ball very quickly. In this situation, the range of the allowable gap is rather wide because the player will not notice the gap between the ball and the virtual head trajectory. On the contrary, take a situation in which the player swings a putter. A putter is swung slowly and the player can catch the movement of the virtual head at the moment he hits the ball. Thus, the range of the allowable gap is nearly zero for a putter. Otherwise, the player feels incongruity.
According to yet another aspect of the present invention, a game method is employed in a game device in which a real interface operated by a player within a real space is represented by the virtual interface device within a virtual interface device.
According to yet another aspect of the present invention, a game program is provided that causes a computer to execute each of the steps of the method cited above. Further, computer-readable storage media on which this program is recorded are also included in the scope of the present invention. Examples of compute-readable recording media include, but are not limited to, flexible discs, hard discs, semiconductor memory, CD-ROMs, DVDs, magnet-optical discs (MOs), and other computer read/writeable recording media.
According to yet another aspect of the present invention, a game system is provided in which a real interface device operated by a player within a real space is represented by a virtual interface device within a virtual space.
These and other objects, features, aspects and advantages of the present invention will become apparent to those skills in the art from the following details description, which, taken in conjunction with the annexed drawings, discloses a preferred embodiment of the present invention.